The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 25, 2005
Filed:
Jan. 07, 2003
Hajime Oguma, Yokohama, JP;
Hajime Oguma, Yokohama, JP;
Nissan Motor Co., Ltd., Yokohama, JP;
Abstract
In order to improve an exhaust gas purification performance immediately after a cold engine is started, firstly for HC purification, an air-fuel ratio is controlled to be in a lean range immediately after the engine start. Next for NOx purification, the air-fuel ratio is switched to be from lean to rich based upon a parameter (engine load, namely, fuel injection amount) related to NOx density at an engine exit or a parameter (catalyst temperature or water temperature) related to the catalyst temperature. The air-fuel ratio to be rich is set as a plurality of values based upon the parameter and as a richer range as the parameter shows high density or high temperature.